<?php namespace Zmsun\Http\Header;class AcceptRanges implements IHeader{protected$rangeUnit=null;public static function fromString($headerLine){$header=new static();list($name,$value)=GenericHeader::splitHeaderLine($headerLine);if(strtolower($name)!=='accept-ranges'){throw new \InvalidArgumentException('Invalid header line for Accept-Ranges string');}$header->rangeUnit=trim($value);return$header;}public function getFieldName(){return'Accept-Ranges';}public function getFieldValue(){return$this->getRangeUnit();}public function setRangeUnit($rangeUnit){$this->rangeUnit=$rangeUnit;return$this;}public function getRangeUnit(){return$this->rangeUnit;}public function toString(){return'Accept-Ranges: '.$this->getFieldValue();}}